Efficacy of slow-release nifedipine on myocardial ischemic episodes in variant angina pectoris

Am J Cardiol. 1991 Sep 1;68(6):580-4. doi: 10.1016/0002-9149(91)90347-n.


To evaluate the efficacy of slow-release nifedipine (a single dose of 20 mg given at 10 P.M. or 2 doses of 20 mg at 10 P.M. and 6 A.M.) on ischemic episodes in patients with variant angina, a single-blind crossover study with ambulatory electrocardiographic monitoring was performed in 15 patients (13 men and 2 women, mean age 63 years). In all, there were 646 ischemic episodes detected with ambulatory electrocardiographic monitoring during the study period, and 618 episodes of them occurred during placebo periods with a circadian variation. Sixty-nine percent of the episodes in placebo periods were asymptomatic. The number of anginal attacks, nitroglycerin tablets taken, ST-segment elevation and the total ischemic duration significantly decreased during nifedipine therapy compared with results after the placebo therapy period, respectively (p less than 0.01 or 0.05). Twenty-eight ischemic episodes occurred during nifedipine therapy when the plasma level of nifedipine was low. Thus, asymptomatic ischemic episodes more frequently occur than symptomatic episodes and the administration of slow-release nifedipine is highly effective in suppressing not only symptomatic but also asymptomatic myocardial ischemia in patients with variant angina. The timing of the administration of slow-release nifedipine is an important factor in suppressing ischemic episodes.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Aged
  • Aged, 80 and over
  • Angina Pectoris, Variant / drug therapy*
  • Circadian Rhythm
  • Coronary Disease / physiopathology*
  • Delayed-Action Preparations
  • Electrocardiography / drug effects
  • Electrocardiography, Ambulatory
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myocardial Infarction / physiopathology
  • Nifedipine / administration & dosage
  • Nifedipine / blood
  • Nifedipine / therapeutic use*
  • Nitroglycerin / administration & dosage
  • Nitroglycerin / therapeutic use
  • Placebos
  • Single-Blind Method
  • Time Factors


  • Delayed-Action Preparations
  • Placebos
  • Nitroglycerin
  • Nifedipine